1. Field of the Invention
The invention concerns a system for the application of glue to a moving web, in particular a strip-like cigarette paper web in a continuous cigarette-making machine. The moving web may also be folding box blanks and the invention may also be used in a cigarette-packing machine. The system includes a contact glue nozzle which is connected to a reservoir filled with glue. The glue may be delivered by a conveying arrangement from the reservoir to the contact glue nozzle and may be conveyed out of an outlet opening in the region of the latter and applied to the web moving past the contact glue nozzle.
The invention also concerns a method for the application of glue to a moving web, in particular a strip-like cigarette paper web in a continuous cigarette-making machine. The moving web may also be folding box blanks and the invention may be utilized in a cigarette-packing machine. In the method, the web may move optionally continuously or intermittently and may be conveyed past a contact glue nozzle and provided with glue by way of the contact glue nozzle.
2. Discussion of Background Information
In cigarette manufacture, single or multiple tobacco strings are wrapped in cigarette paper which, after the application of glue, is closed to form the final cigarette string. In the manufacture of cigarette packs, the folding box blanks are provided with glue at predefined points. For the application of glue, the strip-like cigarette paper or an exposed edge thereof, the folding box blanks or other webs are conveyed past a device for the application of glue or, to be more precise, a glue nozzle. Usually this contact glue nozzle abuts against the moving web, namely e.g. the cigarette paper, and applies the glue to the cigarette paper conveyed continuously past the contact glue nozzle.
In the application of glue to other moving webs, e.g., folding box blanks, the contact glue nozzle can also be arranged a short distance from the folding box blanks which are moving intermittently past the contact glue nozzle. In the application of glue to the cigarette paper, the folding box blanks or the like, however, lingering soiling of the contact glue nozzle occurs. In particular, so-called “glue runs” form behind the contact glue nozzle in the direction of transport of the moving web, and usually at an acute angle formed by an outer wall of the contact glue nozzle and the moving web. These glue runs, which slowly get bigger and additionally carry dust, break off without definition after some time and are entrained in the direction of transport of the cigarette paper upon the application of glue to the cigarette paper. In the process, the string frequently breaks, which in turn leads to stoppage of the machine. In the application of glue to folding box blanks, glue runs referred to as stalagmites and stalactites form from the excess glue, e.g., between the contact glue nozzle and the blanks, leading to blockage of the nozzle and interruption of the process.